Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Finisar (Nasdaq: FNSR) fell nearly 14% in early trading and closed off 12.6%. The optical-networking specialist reported mixed fiscal second-quarter results and a disappointing Q3 outlook.

So what: Finisar earned $0.23 a share of Non-GAAP profit on $241.5 million in revenue in Q2. Analysts were expecting $0.22 and $242.2 million, respectively, according to data compiled by Yahoo! Finance.

Now what: Finisar wasn't the only loser among optical networkers. Investors sold shares of Oclaro (Nasdaq: OCLR) and NeoPhotonics (Nasdaq: NPTN), too -- both stocks were off more than 8%. Do you believe the drops were deserved? Or are you buying Finisar and its peers at current prices? Please weigh in using the comments box below.

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Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team. He didn't own shares in any of the companies mentioned in this article at the time of publication. Check out Tim's portfolio holdings and Foolish writings, or connect with him on Google+ or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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